JP7409956B2 - Substrate processing equipment and substrate processing method - Google Patents

Description

The present invention relates to a substrate processing apparatus and a substrate processing method.

In the process of manufacturing semiconductor devices, various processes are performed on semiconductor wafers using a substrate processing apparatus. For example, as a substrate processing apparatus, an etching apparatus is known in which the thickness of a target film included in a semiconductor wafer is set to a target thickness. For example, an etching apparatus supplies an etching liquid to a semiconductor wafer to etch the semiconductor wafer.

The etching apparatus may include a film thickness measuring device. The film thickness measuring device measures the film thickness of the film to be processed. An etching apparatus equipped with a film thickness measuring device ends the etching process when it is detected that the film thickness measured by the film thickness measuring device has reached a target film thickness (see, for example, Patent Document 1).

Japanese Patent Application Publication No. 2017-85174

However, film thickness measuring instruments have measurement limits. Therefore, if the target film thickness exceeds the measurement limit of the film thickness measuring device, the film thickness of the film to be processed cannot be accurately set to the target film thickness.

The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a substrate processing apparatus that can increase the thickness of a film to be processed to a thickness that exceeds the measurement limit of a film thickness measuring device with higher accuracy; and a substrate processing method.

A substrate processing apparatus according to the present invention includes a substrate holding section, a substrate rotation section, a liquid supply section, a film thickness measuring device, and a control section. The substrate holding section holds the substrate horizontally. The substrate rotating section rotates the substrate and the substrate holding section together about a central axis extending in the vertical direction. The liquid supply section supplies an etching liquid toward the substrate that rotates together with the substrate holding section. The film thickness measuring device measures the film thickness of a film to be processed included in the substrate. The control unit may set the film thickness measured by the film thickness measurement device to a target set according to measurement accuracy of the film thickness measurement device when the etching solution is supplied by the liquid supply unit. Determine whether the film thickness value has been reached. When the control unit determines that the film thickness measured by the film thickness measuring device has reached the target film thickness value while the etching liquid is being supplied by the liquid supply unit, the control unit continues the predetermined process. The supply of the etching liquid by the liquid supply unit is continued until a time elapses, and when the processing duration time has elapsed, the supply of the etching liquid by the liquid supply unit is stopped, and the film thickness of the film to be processed is reduced. The film thickness is reduced to a value exceeding the measurement limit of the film thickness measuring device.

In one embodiment, the control unit sets the processing continuation time based on a target film thickness correction value for correcting the target film thickness value, an etching rate, and a standby etching amount. The target film thickness value corrected by the target film thickness correction value indicates a film thickness value that exceeds the measurement limit of the film thickness measuring device. The etching amount during standby indicates the amount by which the film thickness of the film to be processed is reduced by the etching solution during the standby time. The standby time indicates a time period during which the film to be processed is etched by the etching liquid remaining on the substrate after the liquid supply unit stops supplying the etching liquid.

In one embodiment, the control unit sets the processing duration based on a rotation speed of the substrate, an etching rate, and a target film thickness correction value that corrects the target film thickness value. The target film thickness value corrected by the target film thickness correction value indicates a film thickness value that exceeds the measurement limit of the film thickness measuring device.

In one embodiment, the control unit calculates a film thickness displacement acceleration indicating an acceleration at which the film thickness decreases based on the film thickness measured by the film thickness measuring device. The control unit corrects at least one of the processing continuation time and the rotation speed of the substrate based on the film thickness displacement acceleration.

In one embodiment, the control unit obtains the film thickness measured by the film thickness measuring device during processing of the substrate to be processed, which is the substrate currently being processed. The control unit calculates a film thickness displacement acceleration indicating an acceleration at which the film thickness decreases based on the film thickness measured by the film thickness measuring device. The control unit corrects at least one of the processing continuation time and the rotation speed of the substrate based on the film thickness displacement acceleration before processing the next substrate.

In one embodiment, the substrate processing apparatus further includes a moving section that sequentially moves the liquid supply section to a plurality of stop positions along a horizontal direction. The liquid supply section stops moving and supplies the etching liquid at each of the plurality of stop positions. The plurality of stop positions include a final stop position of the movement of the liquid supply section. The control unit controls the film thickness measured by the film thickness measuring device when the liquid supply unit is supplying the etching solution at a stop position other than the final stop position among the plurality of stop positions. When reaches the target film thickness value, the supply of the etching liquid by the liquid supply section is stopped.

The substrate processing method according to the present invention includes a step of horizontally holding a substrate in a substrate holder, a step of rotating the substrate and the substrate holder together about a central axis extending in the vertical direction, and a step of rotating the substrate and the substrate holder together about a central axis extending in the vertical direction. a step of supplying an etching solution toward the substrate that rotates together with the unit; and a step of measuring the film thickness of the film to be processed included in the substrate using a film thickness measuring device while the etching solution is being supplied. and whether or not the film thickness measured by the film thickness measuring device while the etching solution is being supplied has reached a target film thickness value set according to the measurement accuracy of the film thickness measuring device. and when it is determined that the film thickness measured by the film thickness measuring device has reached the target film thickness value while the etching solution is being supplied , a predetermined processing continuation time is determined. a step of continuing the supply of the etching solution until the processing duration time has elapsed, and stopping the supply of the etching solution after the processing duration time has elapsed, and measuring the film thickness of the film to be processed by measuring the measurement limit of the film thickness measuring device. and a step of reducing the film thickness to a value exceeding the above value.

According to the substrate processing apparatus and the substrate processing method according to the present invention, it is possible to more accurately increase the thickness of the film to be processed to a thickness that exceeds the measurement limit of a film thickness measuring device.

1 is a schematic diagram of a substrate processing apparatus according to Embodiment 1 of the present invention. 1 is a schematic diagram of a processing unit included in a substrate processing apparatus according to Embodiment 1 of the present invention. (a) is a plan view showing probe movement processing. (b) is a plan view showing the film thickness measurement process. (a) is a block diagram showing the configuration of a control device. (b) is a diagram showing an example of an input screen. (a) is a sectional view showing an example of a substrate. (b) is a sectional view showing another example of the substrate. 3 is a flowchart showing processing by a control unit included in the substrate processing apparatus according to Embodiment 1 of the present invention. 3 is a flowchart showing an etching process. FIG. 3 is a diagram showing changes in film thickness of a film to be processed. It is a figure which shows an example of waiting time. 7 is a flowchart showing processing by a control unit included in the substrate processing apparatus according to Embodiment 2 of the present invention. It is a schematic diagram of an etching liquid supply part. FIG. 3 is a schematic diagram of a processing unit included in a substrate processing apparatus according to Embodiment 3 of the present invention. FIG. 3 is a plan view showing an etching solution supply process. (a) is a diagram showing first table information. (b) is a diagram showing second table information. FIG. 3 is a diagram showing an example of a change in film thickness of a film to be processed. It is a figure which shows another example of the change of the film thickness of a film to be processed. 3 is a flowchart showing an etching process.

Embodiments of the present invention will be described below with reference to the drawings (FIGS. 1 to 17). However, the present invention is not limited to the following embodiments. Note that the description may be omitted as appropriate for parts where the description overlaps. Further, in the figures, the same or corresponding parts are given the same reference numerals and the description will not be repeated.

The "substrates" to be processed by the substrate processing apparatus and substrate processing method according to the present invention include semiconductor wafers, photomask glass substrates, liquid crystal display glass substrates, plasma display glass substrates, and FEDs (Field Emission Displays). Various types of substrates such as optical disk substrates, optical disk substrates, magnetic disk substrates, and magneto-optical disk substrates can be applied. In the following, the present embodiment will be mainly described using as an example a substrate processing apparatus and a substrate processing method that process a disk-shaped semiconductor wafer. It is also applicable to various types of substrates other than the above. Further, the shape of the substrate is not limited to a disk shape, and the substrate processing apparatus and substrate processing method according to the present invention can be applied to substrates of various shapes.

[Embodiment 1]
Embodiment 1 of the present invention will be described below with reference to FIGS. 1 to 9. First, a substrate processing apparatus 100 of this embodiment will be explained with reference to FIG. FIG. 1 is a schematic diagram of a substrate processing apparatus 100 of this embodiment. Specifically, FIG. 1 is a schematic plan view of the substrate processing apparatus 100. The substrate processing apparatus 100 processes a substrate W. More specifically, the substrate processing apparatus 100 is a single-wafer type apparatus that processes the substrates W one by one.

As shown in FIG. 1, the substrate processing apparatus 100 includes a plurality of processing units 1, a fluid cabinet 100A, a plurality of fluid boxes 100B, a plurality of load ports LP, an indexer robot IR, a center robot CR, A control device 101 is provided.

Each of the load ports LP accommodates a plurality of stacked substrates W. The indexer robot IR transports the substrate W between the load port LP and the center robot CR. The center robot CR transports the substrate W between the indexer robot IR and the processing unit 1. Note that a mounting table (pass) on which the substrate W is temporarily placed is provided between the indexer robot IR and the center robot CR, and a mounting table (pass) is provided between the indexer robot IR and the center robot CR. It is also possible to adopt an apparatus configuration in which the substrate W is transferred indirectly.

The plurality of processing units 1 form a plurality of towers TW (four towers TW in FIG. 1) arranged so as to surround the center robot CR in plan view. Each tower TW includes a plurality of processing units 1 (three processing units 1 in FIG. 1) stacked one above the other. Each of the processing units 1 supplies a processing liquid to the substrate W to process the substrate W.

Fluid cabinet 100A accommodates processing liquid. Each fluid box 100B corresponds to one of the plurality of towers TW. The processing liquid in the fluid cabinet 100A is supplied to all processing units 1 included in the tower TW corresponding to the fluid box 100B via one of the fluid boxes 100B.

In this embodiment, the processing liquid includes an etching liquid and a rinsing liquid. The etching solution etches the substrate W. Examples of the etching solution include hydrofluoric nitric acid (a mixture of hydrofluoric acid (HF) and nitric acid (HNO ₃ )), hydrofluoric acid, buffered hydrofluoric acid (BHF), ammonium fluoride, and HFEG (a mixture of hydrofluoric acid and ethylene glycol). ) or phosphoric acid (H ₃ PO ₄ ). The rinsing liquid rinses the substrate W. Specifically, the rinsing liquid is used to wash away the etching liquid remaining on the substrate W. The rinsing liquid is, for example, deionized water, carbonated water, electrolyzed ionized water, hydrogen water, ozone water, or hydrochloric acid water with a diluted concentration (for example, about 10 ppm to 100 ppm).

Next, the control device 101 will be explained. The control device 101 controls the operation of each part of the substrate processing apparatus 100. For example, the control device 101 controls the load port LP, indexer robot IR, and center robot CR. Control device 101 includes a control section 102 and a storage section 103.

Control unit 102 has a processor. The control unit 102 includes, for example, a CPU (Central Processing Unit) or an MPU (Micro Processing Unit). Alternatively, the control unit 102 may include a general-purpose computing machine.

Storage unit 103 stores data and computer programs. The data includes recipe data. The recipe data includes information indicating multiple recipes. Each of the plurality of recipes defines processing contents and processing procedures for the substrate W.

Storage unit 103 has a main storage device. The main storage device is, for example, a semiconductor memory. The storage unit 103 may further include an auxiliary storage device. The auxiliary storage device includes, for example, at least one of a semiconductor memory and a hard disk drive. Storage unit 103 may include removable media. The control unit 102 controls the operation of each unit of the substrate processing apparatus 100 based on the computer program and data stored in the storage unit 103.

Next, with reference to FIGS. 1 and 2, the substrate processing apparatus 100 of this embodiment will be further described. FIG. 2 is a schematic diagram of the processing unit 1 included in the substrate processing apparatus 100 of this embodiment. Specifically, FIG. 2 is a schematic cross-sectional view of the processing unit 1.

As shown in FIG. 2, the processing unit 1 includes a chamber 2, a spin chuck 3, a spin motor section 5, a film thickness measuring section 8, a probe moving mechanism 9, and a plurality of guards 10 (two guards in FIG. 2). A guard 10), a first nozzle 41, and a second nozzle 71 are provided. Further, the substrate processing apparatus 100 includes an etching liquid supply section 4 and a rinsing liquid supply section 7. The etching liquid supply section 4 has a first supply pipe 42 , and the rinsing liquid supply section 7 has a second supply pipe 72 . The control device 101 (control section 102) controls the spin chuck 3, the spin motor section 5, the film thickness measurement section 8, and the probe moving mechanism 9.

The chamber 2 has a substantially box shape. The chamber 2 includes a substrate W, a spin chuck 3, a spin motor part 5, a plurality of guards 10, a film thickness measurement part 8, a probe moving mechanism 9, a first nozzle 41, a second nozzle 71, and a part of the first supply pipe 42. , and a part of the second supply pipe 72.

The spin chuck 3 holds the substrate W horizontally. The spin chuck 3 is an example of a substrate holding section. Specifically, the spin chuck 3 includes a plurality of chuck members 32 and a spin base 33. A plurality of chuck members 32 are provided on the spin base 33 along the periphery of the substrate W. The plurality of chuck members 32 hold the substrate W in a horizontal position. The spin base 33 has a substantially disk shape and supports the plurality of chuck members 32 in a horizontal position.

The spin motor unit 5 rotates the substrate W and the spin chuck 3 together about the first rotation axis AX1. The first rotation axis AX1 extends in the vertical direction. In this embodiment, the first rotation axis AX1 extends substantially vertically. The first rotation axis AX1 is an example of a central axis, and the spin motor section 5 is an example of a substrate rotation section. Specifically, the spin motor section 5 rotates the spin base 33 around the first rotation axis AX1. Therefore, the spin base 33 rotates around the first rotation axis AX1. As a result, the substrate W held by the spin chuck 3 rotates about the first rotation axis AX1.

Specifically, the spin motor section 5 includes a motor main body 51, a shaft 53, and an encoder 55. Shaft 53 is coupled to spin base 33. The motor body 51 rotates the shaft 53. As a result, the spin base 33 rotates.

The encoder 55 detects the rotational position of the substrate W and outputs a signal indicating the rotational position of the substrate W to the control device 101 (control unit 102). Hereinafter, a signal indicating the rotational position of the substrate W will be referred to as a "rotational position signal." The control unit 102 detects the rotational speed of the substrate W or the rotational speed [rpm] of the substrate W based on the rotational position signal.

The first nozzle 41 supplies etching liquid to the substrate W from above the substrate W. Specifically, the first nozzle 41 discharges the etching liquid toward the rotating substrate W. The first nozzle 41 is an example of a liquid supply section. The first nozzle 41 discharges the etching liquid in a stationary state. The first nozzle 41 is sometimes referred to as a fixed nozzle. Note that the first nozzle 41 may be a scan nozzle.

The etching liquid supply unit 4 supplies an etching liquid to the first nozzle 41 . Specifically, the etching liquid is supplied to the first nozzle 41 via the first supply pipe 42. The first supply pipe 42 is a tubular member through which the etching solution flows.

The second nozzle 71 supplies a rinse liquid to the substrate W from above the substrate W. Specifically, the second nozzle 71 discharges the rinsing liquid toward the rotating substrate W. The second nozzle 71 discharges the rinse liquid in a stationary state. In other words, the second nozzle 71 is a fixed nozzle. Note that the second nozzle 71 may be a scan nozzle.

The rinse liquid supply section 7 supplies the second nozzle 71 with the rinse liquid. Specifically, the rinsing liquid is supplied to the second nozzle 71 via the second supply pipe 72. The second supply pipe 72 is a tubular member through which the rinsing liquid flows.

Each of the guards 10 has a substantially cylindrical shape. The plurality of guards 10 receive the etching liquid and the rinsing liquid discharged from the substrate W.

The film thickness measurement unit 8 measures the film thickness of the processing target film TG included in the substrate W, and generates a measurement signal indicating the measurement result. The measurement signal (measurement result) indicates the film thickness value of the film TG to be processed. The film thickness value is the value of the thickness of the film. The film thickness measuring unit 8 measures the film thickness of the film to be processed TG in a non-contact manner. The measurement signal is input to the control device 101 (control unit 102).

The film to be processed TG is, for example, a substrate body (for example, a substrate body made of silicon) or a film formed on the surface of the substrate body. The film formed on the surface of the substrate body is, for example, a film made of the same material as the substrate body (for example, a layer made of silicon), or a film made of a different material from the substrate body (for example, a silicon oxide film, a silicon nitride film, or resist).

The film thickness measuring unit 8 measures the film thickness of the film to be processed TG by, for example, spectroscopic interferometry. Specifically, the film thickness measuring section 8 includes an optical probe 81, a signal line 83, and a film thickness measuring device 85.

Optical probe 81 has a lens. The signal line 83 optically connects the optical probe 81 and the film thickness measuring device 85. The signal line 83 includes, for example, an optical fiber. The film thickness measuring device 85 has a light source and a light receiving element. The light emitted from the light source of the film thickness measuring device 85 is emitted to the substrate W via the signal line 83 and the optical probe 81. The light reflected by the substrate W is received by the light receiving element of the film thickness measuring device 85 via the optical probe 81 and the signal line 83.

The film thickness measuring device 85 analyzes the light received by the light receiving element and calculates the film thickness value of the film to be processed TG. The film thickness measuring device 85 generates a measurement signal indicating the calculated film thickness value. The measurement signal is output to the control device 101 (control unit 102). Note that the film thickness measuring device 85 has a measurement limit. Therefore, the film thickness measuring device 85 cannot measure a film thickness that exceeds the measurement limit. For example, the measurement limit of the film thickness measuring device 85 is 1 μm. When the measurement limit of the film thickness measuring device 85 is 1 μm, the film thickness measuring device 85 cannot measure a film thickness of less than 1 μm.

The probe moving mechanism 9 moves the optical probe 81 in a substantially horizontal direction. Specifically, the probe moving mechanism 9 moves the optical probe 81 along the circumferential direction centered on the second rotation axis AX2 along the substantially vertical direction.

Specifically, the probe moving mechanism 9 includes a probe arm 91, a first rotation shaft 93, and a first drive section 95. Probe arm 91 extends substantially horizontally. An optical probe 81 is arranged at the tip of the probe arm 91. Probe arm 91 is coupled to first rotation shaft 93 . The first rotating shaft 93 extends substantially vertically.

The first drive unit 95 rotates the first rotation shaft 93 about the second rotation axis AX2, and rotates the probe arm 91 about the first rotation axis 93 along a substantially horizontal plane. As a result, the optical probe 81 moves along a substantially horizontal plane. Specifically, the optical probe 81 moves around the first rotation axis 93 along the circumferential direction centered on the second rotation axis AX2. The first drive unit 95 includes, for example, a stepping motor. Alternatively, the first drive section 95 may include a motor and a speed reducer.

Next, the probe movement process and the film thickness measurement process will be described with reference to FIGS. 3(a) and 3(b). The probe movement process indicates a process of moving the optical probe 81 to the measurement position P. The measurement position P indicates the position at which the thickness of the film to be processed TG is measured. FIG. 3(a) is a plan view showing the probe movement process. FIG. 3(b) is a plan view showing the film thickness measurement process.

First, the probe movement process will be explained with reference to FIG. 3(a). The control unit 102 described with reference to FIG. 1 controls the probe moving mechanism 9 to move the optical probe 81 to the measurement position P before performing the etching process. In this embodiment, the probe movement process is performed while the substrate W is rotating. However, the probe moving process only needs to be executed before the etching process. For example, the probe movement process may be executed before the substrate W starts rotating.

As shown in FIG. 3A, the probe moving mechanism 9 can move the optical probe 81 along an arcuate trajectory TJ1 in plan view. The trajectory TJ1 passes through the edge portion EG of the substrate W and the center portion CT of the substrate W. The edge portion EG indicates the peripheral portion of the substrate W. The probe moving mechanism 9 moves the optical probe 81 along the trajectory TJ1 to a predetermined measurement position P. The measurement position P is stored in advance in the storage unit 103 described with reference to FIG.

Next, the film thickness measurement process will be explained with reference to FIG. 3(b). The film thickness measurement process is performed during the etching process. As shown in FIG. 3(b), the optical probe 81 is placed at the measurement position P during execution of the film thickness measurement process. In other words, the position of the optical probe 81 is fixed at the measurement position P during execution of the film thickness measurement process.

The film thickness measuring unit 8 measures the film thickness value of the film to be processed TG at a measurement position P (a fixed position) during the etching process. The substrate W rotates during the etching process. Therefore, the film thickness measurement unit 8 measures the film thickness value of the film to be processed TG along the circumferential direction CD of the substrate W. As a result, the measurement signal indicates a distribution (profile) of film thickness values of the film to be processed TG in the circumferential direction CD of the substrate W.

Next, the control device 101 will be explained with reference to FIG. 4(a). FIG. 4(a) is a block diagram showing the configuration of the control device 101. As shown in FIG. 4A, the control device 101 further includes an input section 104 and a display section 105.

The input unit 104 receives an input operation by a worker and outputs information indicating the input content to the control unit 102. Input unit 104 includes, for example, a touch panel and a pointing device. The touch panel is arranged, for example, on the display surface of the display unit 105. The input unit 104 and the display unit 105 constitute, for example, a graphical user interface. In this embodiment, the input unit 104 receives an input operation for inputting a target film thickness value Th1, a target film thickness correction value Thc, and a processing continuation time T1, which will be explained with reference to FIG. 4(b).

Display unit 105 displays various information. In this embodiment, the display unit 105 displays an input screen G (see FIG. 4(b)) that accepts input operations by the operator. The display unit 105 includes, for example, a liquid crystal display or an organic EL (electroluminescence) display.

Next, the input screen G displayed on the display unit 105 will be described with reference to FIG. 4(b) and FIG. 5(a). FIG. 4B is a diagram showing an example of the input screen G. FIG. 5A is a cross-sectional view showing an example of the substrate W. In the example shown in FIG. 5(a), the film to be processed TG is the substrate body.

The input screen G is used for input operations to input the target film thickness value Th1 (see FIG. 5(a)), the target film thickness correction value Thc (see FIG. 5(a)), and the processing duration time T1. As shown in FIG. 4(b), the input screen G displays a first input box 701, a second input box 702, a third input box 703, and an OK button 704.

The OK button 704 is a button for registering the information input on the input screen G. When the operator operates the input unit 104 and inputs an instruction to press the OK button 704, the information input on the input screen G is input. Information is registered. Specifically, the information displayed (input) in each of the first input box 701 to third input box 703 is registered.

The first input box 701 receives an input of the target film thickness value Th1 of the film to be processed TG. More specifically, the first input box 701 accepts input of a numerical value according to the measurement accuracy of the film thickness measuring device 85 described with reference to FIG. For example, if the measurement limit of the film thickness measuring device 85 is 1 μm, the first input box 701 accepts values of 1 μm or more in increments of 0.01 μm.

The second input box 702 accepts input of the target film thickness correction value Thc. For example, the second input box 702 accepts the target film thickness correction value Thc in increments of 0.01 μm. The target film thickness correction value Thc is input in order to correct the target film thickness value Th1 to a film thickness value that exceeds the measurement limit of the film thickness measuring device 85. The control unit 102 corrects the target film thickness value Th1 based on the target film thickness correction value Thc. Hereinafter, the target film thickness value Th1 (target film thickness value set according to the measurement accuracy of the film thickness measuring device 85) may be referred to as "first target film thickness value Th1." Further, the corrected target film thickness value Th1 may be described as a "second target film thickness value Th2."

The second target film thickness value Th2 (see FIG. 5(a)) is the true film thickness value desired by the user of the substrate processing apparatus 100. The control unit 102 can calculate the second target film thickness value Th2 by subtracting the target film thickness correction value Thc from the first target film thickness value Th1. For example, when the first target film thickness value Th1 is 1 μm and the target film thickness correction value Thc is 0.5 μm, the second target film thickness value Th2 is 0.5 μm. When the measurement limit of the film thickness measuring device 85 is 1 μm, a film thickness of 0.5 μm is a film thickness value that cannot be measured by the film thickness measuring device 85.

The third input box 703 accepts input of the processing duration T1. The processing continuation time T1 indicates the time during which the supply of the etching solution is continued after the film thickness of the film to be processed TG reaches the first target film thickness value Th1. After the film thickness of the film to be processed TG reaches the first target film thickness value Th1 (for example, 1 μm), the supply of the etching solution is continued until the processing duration T1 has elapsed, thereby increasing the film thickness of the film to be processed TG. can be set to the second target film thickness value Th2 (a film thickness value exceeding the measurement limit of the film thickness measuring device 85) with higher accuracy.

More specifically, when the target film thickness correction value Thc is input into the second input box 702, the control unit 102 calculates the processing duration T1 and inputs the calculated processing duration T1 into the third input box 703. Display. Further, when the processing continuation time T1 is input into the third input box 703, the control unit 102 calculates the target film thickness correction value Thc, and inputs the calculated target film thickness correction value Thc into the second input box 702. Display.

Here, an example of the first calculation process for calculating the process continuation time T1 will be described. When the target film thickness correction value Thc is input to the second input box 702, the control unit 102 performs processing based on the target film thickness correction value Thc, the etching rate for the film to be processed TG, and the standby etching amount. Calculate the duration T1. The standby etching amount indicates the amount by which the film thickness of the film to be processed TG decreases (etching amount) during the standby time T2, that is, the amount by which the film thickness decreases. Hereinafter, the etching rate for the film to be processed TG may be referred to as "etching rate".

Specifically, even after the supply of the etching liquid is stopped, the film to be processed TG is etched by the etching liquid remaining on the substrate W. Since centrifugal force is applied to the etching solution remaining on the substrate W by the rotation of the substrate W, the liquid film of the etching solution becomes thinner over time after the supply of the etching solution is stopped. The standby time T2 indicates the time required for the etching liquid film remaining on the substrate W to become thin enough to not be able to etch the substrate W after the supply of the etching liquid is stopped. The standby etching amount indicates the amount (etching amount) by which the target film TG is etched by the etching solution remaining on the substrate W after the supply of the etching solution is stopped.

When the target film thickness correction value Thc is input to the second input box 702, the control unit 102 controls the processing target film TG during the processing duration T1 based on the target film thickness correction value Thc and the standby etching amount. The amount to be etched (hereinafter referred to as "continuous etching amount") is calculated. For example, the control unit 102 calculates the continuous etching amount by subtracting the standby etching amount from the target film thickness correction value Thc. Then, the control unit 102 calculates the processing continuation time T1 based on the continuous etching amount and the etching rate.

Note that the etching rate and the standby etching amount are stored in advance in the storage unit 103. The storage unit 103 may store etching rates for each type of film to be processed TG.

Next, an example of the second calculation process for calculating the target film thickness correction value Thc will be described. When the process continuation time T1 is input to the third input box 703, the control unit 102 calculates the amount of continuous etching based on the process continuation time T1 and the etching rate. Then, a target film thickness correction value Thc is calculated based on the continuous etching amount and the standby etching amount.

Next, the etching process will be explained with reference to FIG. 2, FIG. 4(a), and FIG. 5(a). When the etching process starts, the film thickness measurement unit 8 measures the film thickness Th of the substrate W (film to be processed TG). Further, when the etching process starts, the first nozzle 41 discharges the etching liquid toward the upper surface Ws of the substrate W.

When the control unit 102 detects that the film thickness Th of the substrate W has reached the first target film thickness value Th1 based on the measurement signal input from the film thickness measurement unit 8, the control unit 102 determines that the film thickness Th of the substrate W has reached the first target film thickness value Th1. 2. The first nozzle 41 continues to discharge the etching liquid so as to reach the target film thickness value Th2. In other words, the first nozzle 41 continues to discharge the etching liquid so that the film thickness Th of the substrate W is further reduced by the target film thickness correction value Thc.

Specifically, when the control unit 102 detects that the film thickness Th of the substrate W has reached the first target film thickness value Th1, the processing continuation time T1 described with reference to FIG. 4(b) elapses. The first nozzle 41 continues discharging the etching liquid until the time. When the processing continuation time T1 has elapsed, the control unit 102 causes the processing to standby until the standby time T2 elapses. As a result, while the waiting time T2 elapses, the film thickness Th of the substrate W is further reduced by the etching solution remaining on the upper surface Ws of the substrate W, and the film thickness Th of the substrate W reaches the second target film thickness value Th2. Become.

Next, another example of the substrate W will be described with reference to FIG. 5(b). FIG. 5(b) is a cross-sectional view showing another example of the substrate W. As shown in FIG. 5(b), the substrate W may include a processing target film TG and a non-processing target film Mx. The non-process target film Mx is, for example, a silicon nitride film or a silicon oxide film.

When the substrate W includes the non-processing target film Mx, the spin chuck 3 described with reference to FIG. 1 holds the substrate W so that the processing target film TG is an upper layer of the non-processing target film Mx. When the substrate W includes the non-processing target film Mx, the etching process may be a process of removing the entire processing target film TG. That is, the second target film thickness value Th2 may be 0 μm. 0 μm is a film thickness value that cannot be measured by the film thickness measuring device 85. Specifically, when removing the entire film to be processed TG, the target film thickness correction value Thc is set to the same value as the first target film thickness value Th1. According to this embodiment, the film thickness of the film to be processed TG can be set to 0 μm with high accuracy. In other words, the entire film to be processed TG can be removed with high precision.

Next, the substrate processing method of this embodiment will be explained with reference to FIGS. 6 to 8. The substrate processing method of this embodiment is executed by the substrate processing apparatus 100 described with reference to FIGS. 1 to 4. FIG. 6 is a flowchart showing processing by the control unit 102 included in the substrate processing apparatus 100 of this embodiment.

The process shown in FIG. 6 is started when the operator operates the input unit 104 to instruct the start of the etching process of the substrate W. When the operator operates the input unit 104 to instruct the start of etching processing of the substrate W, the display unit 105 displays the input screen G described with reference to FIG. 4(b). The operator sets various conditions via the input screen G (step S1). Specifically, as explained with reference to FIG. 4(b), the operator enters the first target film thickness value Th1, the target film thickness correction value Thc, and the processing duration time T1 via the input screen G. Set.

When various conditions are set via the input screen G, the control unit 102 controls the indexer robot IR and the center robot CR to carry the substrate W into the chamber 2 of the processing unit 1 (step S2). The loaded substrate W is held by the spin chuck 3.

When the spin chuck 3 holds the substrate W, the control section 102 controls the spin motor section 5 to rotate the substrate W together with the spin chuck 3 (step S3).

The control unit 102 determines whether the rotational speed [rpm] of the substrate W is stable at a predetermined value based on the rotational position signal. When the rotational speed [rpm] of the substrate W stabilizes at a predetermined value, the control unit 102 controls the probe moving mechanism 9 to move the optical probe 81 to the measurement position P, as described with reference to FIG. 3(a). (step S4).

After fixing the position of the optical probe 81 at the measurement position P, the control unit 102 starts the etching process (step S5).

When the etching process is completed, the control unit 102 controls the rinsing liquid supply unit 7 to supply the rinsing liquid from the second nozzle 71 toward the upper surface Ws of the substrate W (step S6). Specifically, the control unit 102 opens a valve provided in the second supply pipe 72. By supplying the rinsing liquid to the upper surface Ws of the substrate W, the thin remaining etching liquid is removed from the upper surface Ws of the substrate W. Specifically, the etching liquid is swept away from the substrate W by the rinsing liquid and is discharged around the substrate W. As a result, the thin liquid film of the etching liquid on the substrate W is replaced with a liquid film of the rinsing liquid that covers the entire upper surface of the substrate W.

After replacing the etching liquid on the substrate W with the rinsing liquid, the control unit 102 increases the rotation speed of the spin motor unit 5 to dry the substrate W (step S7). Specifically, the rotational speed of the substrate W is made higher than the rotational speed during the etching process and the rinsing process. As a result, a large centrifugal force is applied to the rinsing liquid on the substrate W, and the rinsing liquid adhering to the substrate W is shaken off around the substrate W. In this way, the rinsing liquid is removed from the substrate W and the substrate W is dried.

After a predetermined time has elapsed since the start of high-speed rotation of the substrate W, the control unit 102 stops the rotation of the substrate W by stopping the operation of the spin motor unit 5 (step S8). As a result, the drying process ends. When the drying process is completed, the holding of the substrate W by the spin chuck 3 is released, and the center robot CR carries out the substrate W out of the chamber 2.

When the drying process is completed, the control unit 102 determines whether or not the planned number of substrates W has been processed (step S9). If the control unit 102 determines that the planned number of substrates W has been processed (Yes in step S9), the process shown in FIG. 6 ends. On the other hand, if the control unit 102 determines that the scheduled number of substrates W has not been processed yet (No in step S9), the processes from step S2 onwards are executed again.

Next, the etching process (step S5) will be explained with reference to FIGS. 7 and 8. FIG. 7 is a flowchart showing the etching process (step S5). FIG. 8 is a diagram (graph) showing changes in the film thickness of the film to be processed TG. In FIG. 8, the horizontal axis indicates time. The vertical axis indicates the film thickness of the film to be processed TG.

As shown in FIGS. 7 and 8, when the etching process starts, the control unit 102 controls the etching liquid supply unit 4 to supply the etching liquid from the first nozzle 41 toward the upper surface Ws of the substrate W ( Step S51). Specifically, the control unit 102 opens a valve provided in the first supply pipe 42.

When the supply of the etching solution is started, as shown in FIG. 8, the film thickness of the film to be processed TG decreases over time. The control unit 102 determines whether the thickness of the film to be processed TG has reached the first target thickness value Th1 based on the measurement signal from the film thickness measurement unit 8 (step S52).

When the control unit 102 determines that the film thickness of the film to be processed TG has reached the first target film thickness value Th1 (Yes in step S52), as shown in FIG. The supply of the etching liquid by the 1 nozzle 41 is continued (step S53).

When the processing continuation time T1 has elapsed after the film thickness of the film to be processed TG reaches the first target film thickness value Th1, the control unit 102 controls the etching liquid supply unit 4 to remove the substrate W from the first nozzle 41. The supply of the etching solution to the upper surface Ws is stopped (step S54). Specifically, the control unit 102 closes the valve provided in the first supply pipe 42.

After stopping the supply of the etching solution, the control unit 102 waits for transition from the etching process to the rinsing process until the standby time T2 has elapsed (step S55). As a result, as shown in FIG. 8, from the time when the supply of the etching solution is stopped until the waiting time T2 has elapsed, the film of the processing target film TG is formed by the liquid film of the etching solution remaining on the upper surface Ws of the substrate W. The thickness further decreases and reaches the second target film thickness value Th2. When the standby time T2 has elapsed, the control unit 102 starts the rinsing process (step S6 in FIG. 6).

Embodiment 1 of the present invention has been described above. According to the present embodiment, after the film thickness of the film to be processed TG reaches the first target film thickness value Th1 (measurement limit of the film thickness measuring device 85), the etching solution is supply will continue. Therefore, the film thickness of the film to be processed TG can be set to a film thickness value (second target film thickness value Th2) that exceeds the measurement limit of the film thickness measuring device 85 with higher accuracy. Further, according to the present embodiment, the processing continuation time T1 is set in consideration of the amount of the film to be processed TG to be etched during the standby time T2. Therefore, it is not necessary to avoid the influence of the etching solution remaining on the substrate W by, for example, increasing the rotation speed [rpm] of the substrate W after the processing duration T1 has elapsed.

Note that in this embodiment, the process of etching the substrate body has been described, but the substrate W may have a plurality of target films TG. In this case, the storage unit 103 stores the etching rate for each of the target films TG. Further, the display unit 105 may display an input screen for inputting information regarding the film to be processed TG, and allow the operator to input information regarding the film to be processed TG. The information regarding the processing target films TG includes, for example, information indicating the type of each of the plurality of processing target films TG, information indicating the film thickness of each of the plurality of processing target films TG, and information indicating the multilayer structure consisting of the plurality of processing target films TG. may include information indicating the configuration of.

Further, in the present embodiment, the processing duration T1 is input or calculated by the control unit 102, but the processing duration T1 may be a specified value.

Further, in the present embodiment, the target film thickness correction value Thc is input, but the second target film thickness value Th2 may be input instead of the target film thickness correction value Thc.

Further, in this embodiment, the standby etching amount is a specified value, but the control unit 102 may calculate the standby etching amount. Specifically, the control unit 102 can calculate the standby etching amount based on the rotational speed [rpm] of the substrate W and the etching rate.

FIG. 9 is a diagram (graph) showing an example of the waiting time T2. Specifically, FIG. 9 shows the relationship among the rotational speed [rpm] of the substrate W, the waiting time T2, and the film thickness d of the etching liquid film. Hereinafter, the thickness d of the liquid film of the etching solution may be referred to as "liquid film thickness d." In FIG. 9, the horizontal axis represents time, and the vertical axis represents liquid film thickness d. As shown in FIG. 9, the liquid film thickness d gradually decreases over time. On the other hand, the rate of decrease in the liquid film thickness d varies depending on the rotation speed [rpm] of the substrate W. Specifically, the higher the rotational speed [rpm] of the substrate W, the greater the rate of decrease in the liquid film thickness d. Therefore, the higher the rotation speed [rpm] of the substrate W, the shorter the waiting time T2 becomes.

The control unit 102 can obtain the waiting time T2 based on the rotation speed [rpm] of the substrate W. For example, the control unit 102 may obtain the standby time T2 by referring to a table showing the relationship between the rotation speed [rpm] of the substrate W and the standby time T2, or The waiting time T2 may be obtained based on a formula showing the relationship between the waiting time T2 and the waiting time T2. A table, table, or formula showing the relationship between the rotational speed [rpm] of the substrate W and the waiting time T2 is stored in the storage unit 103 in advance. The control unit 102 can calculate the standby etching amount based on the acquired standby time T2 and etching rate.

[Embodiment 2]
Next, a second embodiment of the present invention will be described with reference to FIGS. 10 and 11. However, matters that are different from Embodiment 1 will be explained, and explanations of matters that are the same as Embodiment 1 will be omitted. Embodiment 2 differs from Embodiment 1 in the etching process (step S5).

FIG. 10 is a flowchart showing processing by the control unit 102 included in the substrate processing apparatus 100 of this embodiment. Specifically, FIG. 10 shows the etching process (step S5). As shown in FIG. 10, when the supply of the etching solution is started (step S51), the control unit 102 calculates the film thickness displacement acceleration based on the film thickness measured by the film thickness measurement unit 8 (step S501). . The film thickness displacement acceleration indicates the acceleration at which the film thickness of the processing target film TG decreases. In other words, the film thickness displacement acceleration indicates an etching rate that changes moment by moment during the etching process.

The control unit 102 corrects at least one of the processing duration T1 and the rotation speed [rpm] of the substrate W based on the film thickness displacement acceleration. In the example shown in FIG. 10, the control unit 102 first determines whether the film thickness displacement acceleration is within a predetermined range (step S502). A value indicating the predetermined range is stored in advance in the storage unit 103. The predetermined range indicates, for example, an allowable error with respect to the etching rate assumed in advance.

If the control unit 102 determines that the film thickness displacement acceleration is within the predetermined range (Yes in step S502), it executes the processing from step S52 described with reference to FIG. 7.

On the other hand, if the control unit 102 determines that the film thickness displacement acceleration is not within the predetermined range (No in step S502), after executing the correction process (step S503), the control unit 102 performs the step described with reference to FIG. Processing from S52 onwards is executed. The correction process is a process of correcting at least one of the process duration T1 and the rotational speed [rpm] of the substrate W.

Specifically, when the film thickness displacement acceleration is smaller than the minimum value in the predetermined range, the etching progresses more slowly than expected. In other words, the etching rate is smaller than expected. In this case, the control unit 102 executes a correction process to extend the process continuation time T1, for example, based on the difference between the minimum value in the predetermined range and the film thickness displacement acceleration. Specifically, the larger the difference between the minimum value in the predetermined range and the film thickness displacement acceleration, the longer the processing duration T1 is made. This correction process can prevent the continuous etching amount from deviating significantly from the expected etching amount. Alternatively, the control unit 102 may reduce the rotation speed [rpm] of the substrate W based on the difference between the minimum value in the predetermined range and the film thickness displacement acceleration. Specifically, the larger the difference between the minimum value in the predetermined range and the film thickness displacement acceleration, the smaller the rotation speed [rpm] of the substrate W. By reducing the rotational speed [rpm] of the substrate W, the waiting time T2 is extended. Therefore, it is possible to prevent the standby etching amount from deviating significantly from the expected etching amount.

Further, if the film thickness displacement acceleration is larger than the maximum value in the predetermined range, the etching progresses faster than expected. In other words, the etching rate is higher than expected. Therefore, the control unit 102 executes a correction process to shorten the process continuation time T1, for example, based on the difference between the maximum value in a predetermined range and the film thickness displacement acceleration. Specifically, the larger the difference between the maximum value in the predetermined range and the film thickness displacement acceleration, the shorter the processing duration T1 is made. This correction process can prevent the continuous etching amount from deviating significantly from the expected etching amount. Alternatively, the control unit 102 may increase the rotation speed [rpm] of the substrate W based on the difference between the maximum value in the predetermined range and the film thickness displacement acceleration. Specifically, the larger the difference between the maximum value in the predetermined range and the film thickness displacement acceleration, the larger the rotation speed [rpm] of the substrate W. By increasing the rotational speed [rpm] of the substrate W, the waiting time T2 becomes shorter. Therefore, it is possible to prevent the standby etching amount from deviating significantly from the expected etching amount.

Embodiment 2 of the present invention has been described above with reference to FIG. According to the present embodiment, before the thickness of the film to be processed TG reaches the first target film thickness value Th1, the processing duration T1 and the rotation speed [rpm] of the substrate W are determined based on the film thickness displacement acceleration. At least one of the above is corrected. Therefore, the thickness of the film to be processed TG included in the current substrate W to be processed can be set to a film thickness value (second target film thickness value Th2) that exceeds the measurement limit of the film thickness measuring device 85 with higher accuracy. I can do it.

Note that in the present embodiment, the control unit 102 compares the film thickness displacement acceleration with a predetermined range, but the control unit 102 may compare the film thickness displacement acceleration with a predetermined value.

Further, in the present embodiment, the control unit 102 performs the correction process on the current substrate W to be processed, but the control unit 102 may perform the correction process on the next substrate W to be processed. Specifically, the control unit 102 determines the processing duration T1 for the next substrate W to be processed and the rotation of the substrate W based on the film thickness displacement acceleration acquired during the etching process for the previous substrate W to be processed. At least one of the number [rpm] and the number [rpm] may be corrected.

Further, in the present embodiment, the control unit 102 corrects at least one of the processing duration T1 and the rotation speed [rpm] of the substrate W, but the control unit 102 corrects the etching solution based on the film thickness displacement acceleration. At least one of the temperature, the flow rate of the etching solution, and the concentration of the etching solution may be corrected. The temperature of the etching solution, the flow rate of the etching solution, and the concentration of the etching solution are parameters that affect the progress of etching (etching rate).

Specifically, when the film thickness displacement acceleration is smaller than the minimum value in the predetermined range, the control unit 102 may increase the temperature of the etching solution or increase the flow rate of the etching solution. Further, when the film thickness displacement acceleration is larger than the maximum value in the predetermined range, the control unit 102 may lower the temperature of the etching solution, reduce the flow rate of the etching solution, or increase the concentration of the etching solution. may be lowered.

FIG. 11 is a schematic diagram of the etching liquid supply section 4. As shown in FIG. As shown in FIG. 11, the etching liquid supply unit 4 further includes a valve 421, a mixing valve 422, and a heater 423.

Valve 421 is arranged in first supply piping 42 . The valve 421 switches between supplying and stopping the supply of the etching liquid to the first nozzle 41 . Specifically, when the valve 421 is opened, the etching liquid is discharged from the first nozzle 41 toward the substrate W. On the other hand, when the valve 421 is closed, the discharge of the etching liquid is stopped. Further, the valve 421 controls the flow rate of the etching liquid flowing downstream from the valve 421 in the first supply pipe 42 . Specifically, the flow rate of the etching solution flowing downstream from the valve 421 is adjusted according to the opening degree of the valve 421. Therefore, the discharge flow rate of the etching liquid is adjusted according to the opening degree of the valve 421. Valve 421 is, for example, a motor valve.

Mixing valve 422 is arranged in first supply piping 42 . When the mixing valve 422 opens, pure water flows into the first supply pipe 42 and the concentration of the etching solution is diluted. The heater 423 heats the etching liquid flowing through the first supply pipe 42 .

The control unit 102 can control the opening degree of the valve 421 to correct the flow rate of the etching liquid. Furthermore, the mixing valve 422 can be opened to dilute (correct) the concentration of the etching solution. Furthermore, the temperature of the etching solution can be corrected by controlling the temperature of the heater 423.

Note that the temperature of the etching solution may be corrected before the thickness of the film to be processed TG reaches the first target film thickness value Th1, or the temperature of the etching solution may be corrected before the film thickness of the film to be processed TG reaches the first target film thickness value Th1. It may be corrected after it is reached. Similarly, the flow rate of the etching liquid and the concentration of the etching liquid may be corrected after the film thickness of the film to be processed TG reaches the first target film thickness value Th1. The correction may be made before the film thickness of the film to be processed TG reaches the first target film thickness value Th1. By correcting at least one of the temperature of the etching solution, the flow rate of the etching solution, and the concentration of the etching solution, the film thickness displacement acceleration before the film thickness of the film to be processed TG reaches the first target film thickness value Th1 can be kept within a predetermined range. In other words, the etching rate before the film thickness of the film to be processed TG reaches the first target film thickness value Th1 can be adjusted to the expected etching rate.

[Embodiment 3]
Next, a third embodiment of the present invention will be described with reference to FIGS. 12 to 17. However, matters that are different from Embodiments 1 and 2 will be explained, and descriptions of matters that are the same as Embodiments 1 and 2 will be omitted. Embodiment 3 differs from Embodiments 1 and 2 in that the first nozzle 41 moves.

First, with reference to FIG. 12, the processing unit 1 in this embodiment will be described. FIG. 12 is a schematic diagram of the processing unit 1 included in the substrate processing apparatus 100 of this embodiment. Specifically, FIG. 12 is a schematic cross-sectional view of the processing unit 1.

As shown in FIG. 12, the processing unit 1 further includes a nozzle moving mechanism 6. The nozzle moving mechanism 6 sequentially moves the first nozzle 41 to a plurality of stop positions along the horizontal direction. The nozzle moving mechanism 6 is an example of a moving section. Specifically, the nozzle moving mechanism 6 moves the first nozzle 41 along the circumferential direction centered on the third axis of rotation AX3 along the substantially vertical direction. The first nozzle 41 stops moving and supplies the etching liquid at each of the plurality of stop positions.

Specifically, the nozzle moving mechanism 6 includes a nozzle arm 61, a second rotation shaft 63, and a second drive section 65. The nozzle arm 61 extends substantially horizontally. The first nozzle 41 is arranged at the tip of the nozzle arm 61. Nozzle arm 61 is coupled to second rotation shaft 63 . The second rotating shaft 63 extends substantially vertically.

The second drive unit 65 rotates the second rotation shaft 63 about the third rotation axis AX3, and rotates the nozzle arm 61 about the second rotation axis 63 along a substantially horizontal plane. As a result, the first nozzle 41 moves along a substantially horizontal plane. Specifically, the first nozzle 41 moves around the second rotation axis 63 along the circumferential direction centered on the third rotation axis AX3. The second drive unit 65 includes, for example, a stepping motor. Alternatively, the second drive unit 65 may include a motor and a speed reducer.

Next, the etching liquid supply process will be described with reference to FIG. 13. FIG. 13 is a plan view showing the etching solution supply process. As shown in FIG. 13, the nozzle moving mechanism 6 can move the first nozzle 41 along an arcuate trajectory TJ2 in plan view. The trajectory TJ2 passes through the edge portion EG of the substrate W and the center portion CT of the substrate W.

In this embodiment, the nozzle moving mechanism 6 sequentially moves the first nozzle 41 to each stop position from the first stop position X1 to the fourth stop position X4 along the trajectory TJ2. The first nozzle 41 discharges etching liquid toward the rotating substrate W at each stop position from the first stop position X1 to the fourth stop position X4. In this embodiment, the fourth stop position X4 indicates the final stop position of the movement of the first nozzle 41.

Next, stop position information will be explained with reference to FIG. 14(a), and moving speed information will be explained with reference to FIG. 14(b). The stop position information indicates the stop position of the first nozzle 41. The moving speed information indicates the moving speed of the first nozzle 41. The control unit 102 controls the nozzle moving mechanism 6 based on the stop position information and the movement speed information to sequentially move the first nozzle 41 to each stop position from the first stop position X1 to the fourth stop position X4. .

FIG. 14(a) is a diagram showing the first table information TB1. The first table information TB1 indicates stop position information. In the first table information TB1, the upper column shows each stop position of the first nozzle 41 (first stop position X1 to fourth stop position X4), and the lower column shows the position of the first nozzle 41 at each stop position. Indicates the stop time (first stop time Tx1 to fourth stop time Tx4). The first table information TB1 is stored in the storage unit 103.

The control unit 102 sequentially moves the first nozzle 41 to each stop position from the first stop position X1 to the fourth stop position X4 by controlling the nozzle moving mechanism 6 with reference to the first table information TB1. .

FIG. 14(b) is a diagram showing the second table information TB2. The second table information TB2 indicates moving speed information. In the second table information TB2, the upper column indicates each movement section of the first nozzle 41. Specifically, the movement section of the first nozzle 41 includes a first section to a third section. The first section indicates a movement section from the first stop position X1 to the second stop position X2. The second section indicates a movement section from the second stop position X2 to the third stop position X3. The third section indicates a movement section from the third stop position X3 to the fourth stop position X4. In the second table information TB2, the lower column shows the moving speed (first moving speed Y1 to third moving speed Y3) of the first nozzle 41 in each moving section. The second table information TB2 is stored in the storage unit 103.

For example, when moving the first nozzle 41 from the first stop position X1 to the second stop position X2, the control unit 102 controls the nozzle moving mechanism 6 with reference to the second table information TB2. The first nozzle 41 is moved at a moving speed Y1.

Next, with reference to FIG. 15, the etching process in this embodiment will be described. FIG. 15 is a diagram (graph) showing an example of a change in the film thickness of the film to be processed TG. In FIG. 15, the horizontal axis represents time, and the vertical axis represents the thickness of the film TG to be processed.

As shown in FIG. 15, the first nozzle 41 supplies the etching liquid to the substrate W at each stop position from the first stop position X1 to the fourth stop position 2 target film thickness value Th2.

Specifically, when the etching process starts, the first nozzle 41 moves to the first stop position X1. The first nozzle 41 discharges the etching liquid while stopped at the first stop position X1 (during the first stop time Tx1).

When the first stop time Tx1 has elapsed, the first nozzle 41 moves to the second stop position X2. While moving from the first stop position X1 to the second stop position X2, the first nozzle 41 stops discharging the etching liquid. The first nozzle 41 discharges the etching liquid while stopped at the second stop position X2 (during the second stop time Tx2).

Thereafter, in the same manner, the first nozzle 41 discharges the etching liquid while stopped at the third stop position X3, and discharges the etching liquid while stopped at the fourth stop position X4.

By the first nozzle 41 supplying the etching liquid to the substrate W at each stop position from the first stop position X1 to the fourth stop position While the etching liquid is being discharged at the fourth stop position X4 (final stop position), the film thickness of the film to be processed TG reaches the first target film thickness value Th1.

When the control unit 102 detects that the film thickness of the film to be processed TG has reached the first target film thickness value Th1, the control unit 102 causes the first nozzle 41 to continue discharging the etching liquid until the processing continuation time T1 has elapsed. At this time, the first nozzle 41 discharges the etching liquid at the fourth stop position X4 (final stop position). When the control unit 102 detects that the processing duration time T1 has elapsed, the control unit 102 stops the first nozzle 41 from discharging the etching liquid.

The control unit 102 causes the process to wait until a standby time T2 elapses after the first nozzle 41 stops discharging the etching liquid. During the standby time T2, the film to be processed TG is etched by the etching solution remaining on the substrate W, and the film thickness of the film to be processed TG becomes the second target film thickness value Th2.

Next, error processing in this embodiment will be explained with reference to FIG. The error process is a process for urgently stopping the supply of etching liquid by the first nozzle 41. Error processing is performed when etching progresses faster than expected. That is, error processing is executed when the etching rate is higher than expected. FIG. 16 is a diagram (graph) showing another example of the change in film thickness of the film to be processed TG. In FIG. 16, the horizontal axis represents time, and the vertical axis represents the thickness of the film TG to be processed.

In the example shown in FIG. 16, the etching progresses faster than expected, and while the first nozzle 41 is discharging the etching liquid at a stop position other than the fourth stop position X4 (final stop position), The film thickness of the film to be processed TG has reached the first target film thickness value Th1. Specifically, while the first nozzle 41 is discharging the etching liquid at the third stop position X3, the film thickness of the film to be processed TG reaches the first target film thickness value Th1.

While the first nozzle 41 is discharging the etching liquid at a stop position other than the fourth stop position When it is detected that Th1 has been reached, error processing is executed.

Specifically, the control unit 102 stops the supply of the etching liquid by the first nozzle 41, and ends the etching process for the substrate W currently being processed. In this embodiment, the control unit 102 further causes the display unit 105 to display an error message. The error message indicates that an error occurred during the etching process.

Next, with reference to FIG. 17, the etching process (step S5) in this embodiment will be described. FIG. 17 is a flowchart showing the etching process (step S5).

As shown in FIG. 17, the control unit 102 causes the film thickness of the film to be processed TG to reach the first target film thickness value Th1 based on the measurement signal input from the film thickness measuring device 85 (film thickness measuring unit 8). If it is determined that the stop position of the first nozzle 41 has been reached (Yes in step S52), it is determined whether the stop position of the first nozzle 41 is the final stop position (in this embodiment, the fourth stop position X4) (step S510).

When the control unit 102 determines that the stop position of the first nozzle 41 is the final stop position (fourth stop position do.

On the other hand, if the control unit 102 determines that the stop position of the first nozzle 41 is not the final stop position (fourth stop position X4) (No in step S510), it executes error processing (step S511). Specifically, as described with reference to FIG. 16, the control unit 102 stops the supply of the etching liquid by the first nozzle 41. In this embodiment, the control unit 102 further causes the display unit 105 to display an error message. After executing the error process, the control unit 102 ends the etching process for the current target substrate W.

The third embodiment of the present invention has been described above with reference to FIGS. 12 to 17. According to this embodiment, the etching solution can be supplied toward the substrate W from a plurality of different positions.

Note that error processing may be omitted. That is, even if the film thickness of the film to be processed TG reaches the first target film thickness value Th1 while the first nozzle 41 is discharging the etching liquid at a stop position other than the final stop position, the processing continuation time T1 The supply of the etching solution may be continued until the processing duration time T1 has elapsed, and etching may be performed using the etching solution remaining on the substrate W during the waiting time T2.

Further, the control unit 102 may calculate the film thickness displacement acceleration described in the second embodiment. In this case, the control unit 102 may increase or decrease the number of stop positions of the first nozzle 41 based on the film thickness displacement acceleration, for example. Alternatively, the control unit 102 may increase or decrease the moving speed of the first nozzle 41 based on the film thickness displacement acceleration. Alternatively, the moving speed may be increased or decreased while increasing or decreasing the stop position.

Specifically, the control unit 102 may increase the number of stop positions of the first nozzle 41 when the film thickness displacement acceleration is smaller than the minimum value in the predetermined range. By increasing the number of stopping positions of the first nozzle 41, the liquid film of the etching solution on the substrate W becomes less likely to become thin. Therefore, the etching rate can be adjusted to the expected etching rate. Alternatively, the control unit 102 may increase the moving speed of the first nozzle 41. By increasing the moving speed of the first nozzle 41, the moving time of the first nozzle 41 from one stop position to the next stop position becomes shorter, so the supply of etching liquid from the first nozzle 41 to the substrate W is stopped. It takes less time to do it. Therefore, the liquid film of the etching solution on the substrate W is less likely to become thin, and the etching rate can be adjusted to the expected etching rate.

Further, the control unit 102 may reduce the number of stop positions of the first nozzle 41 when the film thickness displacement acceleration is larger than the maximum value of the predetermined range. By reducing the number of stopping positions of the first nozzle 41, the liquid film of the etching solution on the substrate W becomes less likely to become thick. Therefore, the etching rate can be adjusted to the expected etching rate. Alternatively, the control unit 102 may reduce the moving speed of the first nozzle 41. By reducing the moving speed of the first nozzle 41, the moving time of the first nozzle 41 from one stop position to the next stop position becomes longer, so the supply of etching liquid from the first nozzle 41 to the substrate W is stopped. It takes longer to do so. Therefore, the film of the etching solution on the substrate W is less likely to become thick, and the etching rate can be adjusted to the expected etching rate.

The embodiments of the present invention have been described above with reference to the drawings (FIGS. 1 to 17). However, the present invention is not limited to the above-described embodiments, and can be implemented in various forms without departing from the spirit thereof. Further, the plurality of components disclosed in the above embodiments can be modified as appropriate. For example, some of the components shown in one embodiment may be added to the components of another embodiment, or some of the components shown in one embodiment may be configured. Elements may be deleted from the embodiment.

The drawings mainly schematically show each component in order to facilitate understanding of the invention, and the thickness, length, number, spacing, etc. of each illustrated component may vary depending on the convenience of drawing. The above image may differ from the actual one. Further, the configuration of each component shown in the above embodiment is an example, and is not particularly limited, and it goes without saying that various changes can be made without substantially departing from the effects of the present invention. .

For example, the spin chuck 3 described with reference to FIG. There is no particular limitation as long as it can be maintained. For example, the spin chuck 3 may be a vacuum type chuck or a Bernoulli type chuck.

Further, although the input screen G described with reference to FIG. 4(b) and FIG. 10 allows the operator to input a numerical value, the operator may select the numerical value from a pull-down menu.

Further, in the embodiments with reference to FIGS. 1 to 17, the target film TG is etched during the standby time T2, but the etching process during the standby time T2 may be omitted. For example, by increasing the rotational speed [rpm] of the substrate W after the processing duration T1 has elapsed, the etching processing during the standby time T2 can be omitted.

The present invention is useful in the field of processing substrates.

1: Processing unit 3: Spin chuck 5: Spin motor section 6: Nozzle moving mechanism 8: Film thickness measuring section 9: Probe moving mechanism 41: First nozzle 81: Optical probe 85: Film thickness measuring device 100: Substrate processing apparatus 101 : Control device 102 : Control part 103 : Storage part 104 : Input part 105 : Display part G : Input screen Mx : Non-processing target film P : Measurement position T1 : Processing continuation time T2 : Standby time TG : Processing target film Th1 : Target Film thickness value (first target film thickness value)
Th2: Second target film thickness value Thc: Target film thickness correction value W: Substrate X1: First stop position X2: Second stop position X3: Third stop position X4: Fourth stop position

Claims (7)

a board holder that holds the board horizontally;
a substrate rotation unit that rotates the substrate and the substrate holding unit together around a central axis extending in the vertical direction;
a liquid supply unit that supplies an etching liquid toward the substrate that rotates together with the substrate holding unit;
a film thickness measuring device that measures the film thickness of a film to be processed included in the substrate;
When the etching solution is being supplied by the liquid supply section, the film thickness measured by the film thickness measuring device reaches a target film thickness value set according to the measurement accuracy of the film thickness measuring device. a control unit that determines whether or not the
Equipped with
When the control unit determines that the film thickness measured by the film thickness measuring device has reached the target film thickness value while the etching liquid is being supplied by the liquid supply unit, the control unit continues the predetermined process. The supply of the etching liquid by the liquid supply unit is continued until a time elapses, and when the processing duration time has elapsed, the supply of the etching liquid by the liquid supply unit is stopped, and the film thickness of the film to be processed is reduced. A substrate processing apparatus that reduces a film thickness to a value that exceeds the measurement limit of the film thickness measuring device. The control unit sets the processing continuation time based on a target film thickness correction value for correcting the target film thickness value, an etching rate, and a standby etching amount;
The target film thickness value corrected by the target film thickness correction value indicates a film thickness value that exceeds the measurement limit of the film thickness measuring device,
The standby etching amount indicates the amount by which the film thickness of the film to be processed is reduced by the etching solution during the standby time,
2. The substrate processing according to claim 1, wherein the standby time indicates a time period during which the film to be processed is etched by the etching solution remaining on the substrate after the supply of the etching solution by the liquid supply unit is stopped. Device. The control unit sets the processing continuation time based on the rotation speed of the substrate, the etching rate, and a target film thickness correction value that corrects the target film thickness value,
The substrate processing apparatus according to claim 1, wherein the target film thickness value corrected by the target film thickness correction value indicates a film thickness value exceeding a measurement limit of the film thickness measuring device. The control unit calculates a film thickness displacement acceleration indicating an acceleration at which the film thickness decreases based on the film thickness measured by the film thickness measuring device, and continues the process based on the film thickness displacement acceleration. The substrate processing apparatus according to claim 1 , wherein at least one of time and rotation speed of the substrate is corrected. The control unit includes:
Obtaining the film thickness measured by the film thickness measuring device during processing of the substrate to be processed, which is the substrate currently being processed;
Based on the film thickness measured by the film thickness measuring device, calculate a film thickness displacement acceleration indicating an acceleration at which the film thickness decreases;
Any one of claims 1 to 3, wherein at least one of the processing duration and the rotation speed of the substrate is corrected based on the film thickness displacement acceleration before processing the next substrate. The substrate processing apparatus described in . further comprising a moving unit that sequentially moves the liquid supply unit to a plurality of stop positions along the horizontal direction,
The liquid supply unit stops moving and supplies the etching liquid at each of the plurality of stop positions,
The plurality of stop positions include a final stop position of the movement of the liquid supply unit,
The control unit controls the film thickness measured by the film thickness measuring device when the liquid supply unit is supplying the etching solution at a stop position other than the final stop position among the plurality of stop positions. The substrate processing apparatus according to any one of claims 1 to 5, wherein the liquid supply unit stops supplying the etching liquid when the film thickness reaches the target film thickness value. a step of holding the substrate horizontally in the substrate holding section;
a step of rotating the substrate and the substrate holding part together around a central axis extending in the vertical direction;
supplying an etching solution toward the substrate that rotates together with the substrate holder;
a step of measuring the film thickness of a film to be processed included in the substrate using a film thickness measuring device while the etching solution is being supplied ;
While the etching solution is being supplied, it is determined whether the film thickness measured by the film thickness measuring device has reached a target film thickness value set according to the measurement accuracy of the film thickness measuring device. a process of determining;
When it is determined that the film thickness measured by the film thickness measuring device has reached the target film thickness value while the etching liquid is being supplied , the etching liquid is supplied until a predetermined processing duration elapses. A process of continuing the supply of
A substrate processing method, comprising: stopping the supply of the etching solution when the processing duration time has elapsed, and reducing the film thickness of the film to be processed to a film thickness value that exceeds the measurement limit of the film thickness measuring device. .

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